1. Field of the Invention
The invention relates generally to household blenders, and more particularly to a household blender having a crushed ice functionality.
2. Description of the Related Art
Culinary blenders are ubiquitous in a conventional commercial or household kitchen. Such appliances typically comprise a selectively closable, open-top reservoir or container having a multiple-bladed cutter assembly at a lower portion of the reservoir which is rotated about a vertical axis by a motor driven shaft extending through the bottom of the reservoir. The blades are typically configured to both pulverize and mix the contents in the reservoir, and are used to process solid and semi-solid food items, liquids, and mixtures of solid and liquid food items. Mixing is most efficiently achieved by a pattern of movement that introduces the entire contents of the reservoir into contact with the rotating blades during the mixing operation.
Conventional countertop blenders frequently include a functionality for processing crushed ice from ice cubes for beverages, deserts, confections, and the like. This functionality typically comprises a timed pulsing pattern, which is initiated by the operator actuating a dedicated ice crushing function switch. The pulsing pattern is typically achieved by cycling the operation of the blender between a preselected duration of “on” time and a preselected duration of “off” time according to a preprogrammed sequence of pulsations. For example, the “on” time may be 0.1 second followed by an “off” time of 0.2 second, which is repeated until the blender is stopped by the operator again actuating the crushed ice function switch.
This preprogrammed “on-off” sequence enables hands-free operation of the blender, but the constant, regular pulsing pattern is not efficient, nor does it always result in properly crushed ice. This is due to the high variation in the properties and quantities of the contents in the reservoir, as well as the changing consistency of the contents during the blending process. If the constant pulsing pattern is too slow, the contents may settle relatively quickly, resulting in excessive “off” time between “on” pulses. This can lead to a total processing time longer than necessary. If the constant pulsing pattern is too fast, the contents will not be allowed to completely settle to the bottom of the reservoir, and the blending performance will consequently be poor because the blades will be unable to efficiently process and mix the contents. These conditions can also leave the ice over crushed or under crushed.
There is a need for a blender having a crushed ice functionality which can accommodate variations in the properties and quantities of the contents in order to optimize the processing and mixing of the contents.